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      <title>锁定模式</title>
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     <img src="../../../images/pythonbook.png"/>
     <h2>书名：<i>《Python从菜鸟到高手》</i></h2>
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     出版社：<u>清华大学出版社</u>
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     <button id="button" onclick="onClick()">进入锁定模式</button>
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